apt-summary/main.py

#!/usr/bin/env python3
import fileinput
import shutil
from dataclasses import dataclass
from enum import Enum
from typing import Union

from packaging import version
from packaging.version import Version, InvalidVersion

from diff import get_diff

# https://www.debian.org/doc/debian-policy/ch-controlfields.html#version

SomeVersion = Union[Version]

lines = list(fileinput.input())


class UpdateType(Enum):
    EPOCH = "Epoch"
    MAJOR = "Major"
    MINOR = "Minor"
    PATCH = "Patch"
    DEBIAN = "Debian"
    OTHER = "Other"


@dataclass
class Update:
    name: str
    old_version: str
    new_version: str
    type: UpdateType


def longest_value(table, column_no):
    return max(len(row[column_no]) for row in table)


def update_type(old_version_str: str, new_version_str: str, depth=0) -> UpdateType:
    try:
        old_version = version.parse(old_version_str.replace(":", "!", 1))
        new_version = version.parse(new_version_str.replace(":", "!", 1))

        if new_version.epoch != old_version.epoch:
            return UpdateType.EPOCH
        if new_version.major != old_version.major:
            return UpdateType.MAJOR
        if new_version.minor != old_version.minor:
            return UpdateType.MINOR
        if new_version.micro != old_version.micro:
            return UpdateType.PATCH
        if new_version.post != old_version.post:
            return UpdateType.DEBIAN
        if depth:
            return UpdateType.DEBIAN
        return UpdateType.OTHER
    except InvalidVersion:
        return UpdateType.OTHER


assert lines[0] == "VERSION 3\n"

updatelines = lines[lines.index('\n') + 1:]
updates = []

for line in updatelines:
    pkg_name, old_version_str, old_arch, _, comparison, new_version_str, new_arch, _, filename = line.split()
    if filename == "**CONFIGURE**":
        continue
    if old_version_str == "-" or new_version_str == "-":
        continue
    type = update_type(old_version_str, new_version_str)
    updates.append(Update(
        pkg_name,
        old_version_str,
        new_version_str,
        type
    ))

text = ""
for update in UpdateType:
    sub_updates = [u for u in updates if u.type == update]
    if not sub_updates:
        continue
    width = shutil.get_terminal_size((80, 20)).columns
    text += update.value.center(width, "-")

    for update in sub_updates:
        diff_text = get_diff(update.old_version, update.new_version)
        text += (
            f"{update.name:<{max(len(u.name) for u in sub_updates)}}"
            " "
            f"{update.old_version:<{max(len(u.old_version) for u in sub_updates)}}"
            " ➜ "
            f"{diff_text:<{max(len(u.old_version) for u in sub_updates)}}"
            "\n"
        )

print(text)